Technical Field
The present invention relates to the general technical field of the transportation of freight, notably the transportation of loads placed on pallets. These loads are for example cars presenting the same or differing outlines.
More specifically, the invention especially concerns the gripper of an assembly or system for locking a palette on a support structure defining a loading space. The grippers of such a locking assembly can advantageously equip a road vehicle of the following types van, trailer, semitrailer, articulated convoy, a container destined to be loaded onto a semitrailer or a container carrier or a wagon.
Such a locking system, comprising such grippers, can also be used within a warehouse or the like.
Description of the Prior Art
It is known, for example, from U.S. Pat. No. 4,597,712 an apparatus for loading and unloading semitrailers. This apparatus is mounted at the rear end of a loading space and comprises articulated arms for laterally gripping a vehicle bearing on wheel supports and for moving the assembly to a loading position. The various operations and movements are controlled by an operator working at a control console.
Such an apparatus, apart from its complexity, has the drawback of being continuously controlled by an operator. In addition, the operator does not always have all of the information necessary for optimal loading, unloading, optimal transportation or distribution imposing special restrictions. It can thus happen that the loads, including vehicles, are placed in non-optimal, even dangerous, loading positions or that the locking of loads onto their support structure is either not performed or is insufficient. This would result in an obvious lack of safety during transportation, in particular at the expense of the integrity of the loads. The operator would be placed in danger when verifying the correct attachment of the loads.
U.S. Pat. No. 5,525,026 A describes a device for storing and/or transporting goods with irregular shapes, such as vehicles and using pallets upon which these vehicles are placed. A crane moving longitudinally along rails within a trailer carries a pallet longitudinally and vertically from a loading area to a selected front storage position and cause the pallet to rotate on a non-vertical axis, so that it passes from a loading position to a transportation position. The crane includes a pre-programmable automatic control which can control the operation of the crane and select positions and storage orientations in order to optimize the use of the space within the trailer. A telescopic pin provided at each end of the pallet allows the pallets to be attached, in a non permanent way, to the walls of the trailer and to be oriented in the desired storage position. To this end, each pin is designed to penetrate one of the receptor orifices distributed within the walls of the trailer. A light source provided behind each hole helps to visually ensure the proper engagement of each telescopic pin within a receptor orifice.
By design, including the fact that it uses a crane for the handling of pallets, the device of U.S. Pat. No. 5,525,0261 A does not allow pallets to be positioned within the upper part of the space within the trailer, especially without having to change it in a way that would greatly exceed the maximum permitted height. This system, using a single pin provided at each corner of the pallet for locking, limits the number of possible positions for the pallets within the locations provided for the receptor orifices distributed within the walls of the trailer. Furthermore, particularly in the case where a pin would not engage with the intended receptor orifice, the palette would not be restrained correctly and would be a source of danger. Similarly the visual inspection means of the locking of each pin, in addition to being cumbersome, bulky, expensive and unreliable, could easily be hindered or damaged and thus completely unusable. This is likely to affect the reliability of the locking.